X-Git-Url: https://git.distorted.org.uk/~mdw/tripe/blobdiff_plain/0f0cfd6d935d979db5f8af200fee0394441c4bd5..HEAD:/svc/conntrack.8.in diff --git a/svc/conntrack.8.in b/svc/conntrack.8.in index 713a70b3..b38f6681 100644 --- a/svc/conntrack.8.in +++ b/svc/conntrack.8.in @@ -85,22 +85,24 @@ followed by peer definitions, each of which looks like this: .B = .RI [ remote-addr ] .IB network / mask +\&... .PP This means that the peer .I tag -should be selected if the host's current IP address is within the -network indicated by +should be selected if the host's current IP address is within one of the +networks indicated by .IB network / mask \fR. -Here, +Here, a .I network -is an IP address in dotted-quad form, and +is an IPv4 or IPv6 address in dotted-quad form, and .I mask -is a netmask, either in dotted-quad form, or as a number of 1-bits. -Only one peer in each group may be connected at any given time; if a -change is needed, any existing peer in the group is killed before -connecting the new one. If no match is found in a particular group, -then no peers in the group are connected. Strange and unhelpful things -will happen if you put the same peer in several different groups. +is a netmask, either in dotted-quad form (for IPv4), or as a prefix +length (i.e., the number of initial 1-bits). Only one peer in each +group may be connected at any given time; if a change is needed, any +existing peer in the group is killed before connecting the new one. If +no match is found in a particular group, then no peers in the group are +connected. Strange and unhelpful things will happen if you put the same +peer in several different groups. .PP The tags .B down @@ -113,36 +115,29 @@ is useful for detecting a `home' network, where a VPN is unnecessary The notion of `current IP address' is somewhat vague. The .B conntrack service calculates it as the source address that the host would put on -an IP packet sent to an arbitrarily chosen remote address. The default -remote address is 1.2.3.4 (which is unlikely ever to be assigned); this -should determine an IP address on the network interface closest to the -default gateway. You can influence this process in two ways. Firstly, -you can change the default remote address used by adding a line +an IP packet sent to a particular remote address; note that this is +entirely hypothetical, and no actual packets are transmitted. The +default remote addresses are 1.2.3.4 (for IPv4, which is unlikely ever +to be assigned), and 2001::1 (for IPv6); this should determine an IP +address on the network interface closest to the default gateway. You +can influence this process in two ways. Firstly, you can change the +default remote address used by adding one or more lines .IP .B "test-addr =" .I remote-addr +\&... .PP before the first peer group section. Secondly, you can specify a particular .I remote-addr to use when checking whether a particular peer is applicable. .PP -The peer definitions can be in any order. They are checked -most-specific first, and searching stops as soon as a match is found. -Therefore a default definition can be added as -.IP -.I tag -.B = -.B 0/0 -.PP -without fear of overriding any more specific definitions. For avoidance -of doubt, one peer definition is -.I more specific -than another if either the former has a specified -.I remote-addr -and the latter has not, or the former is wholly contained within the -latter. (Overlapping definitions are not recommended, and will be -processed in an arbitrary order.) +The peer definitions in each group are checked in the order given, and +searching stops as soon as a match is found. (In older versions of +.BR conntrack , +definitions were processed according to a most-specific-first order, but +that doesn't provide an ordering between IPv4 and IPv6 networks, which +is important; so this has been changed.) .PP Peers are connected using the .BR connect (8)